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This paper proposes a power‐optimized column‐parallel cyclic analog to digital converter (ADC) for complementary metal oxide semiconductors (CMOS) image sensor readout circuits. The design combines a 2.5‐bit/cycle architecture with a comparator shutdown technique based on the comparator‐based switched‐capacitor (CBSC) circuits, which results in a significant reduction in the operating time of the threshold detection comparator compared with conventional CBSC circuits. This reduction in operating time leads to power savings as the threshold detection comparator can be shut down quickly. The paper also presents a comprehensive analysis of the nonideal factors of CBSC circuits and the coarse and fine conversion allocation scheme. The 10‐bit two‐stage comparator‐based cyclic ADC is designed in a 110 nm 1P4 M CMOS technology. Simulation results show that the effective number of bit (ENOB) is 9.7 bits, with each column consuming 103 μ$$ \upmu $$W of power. The proposed cyclic ADC has a figure of merit (FOM) of 123 fJ/conv‐step. Compared with conventional structures, the proposed design reduces the power consumption of the ADC by 34.3% while maintaining the same level of performance. [ABSTRACT FROM AUTHOR]

Let k$k$ be a number field. For a variety X$X$ over k$k$ that satisfies weak approximation with Brauer–Manin obstruction, we study the same property for smooth projective models of its symmetric products. Based on the same method, we also explore the property of weak approximation with Brauer–Manin obstruction for norm varieties. [ABSTRACT FROM AUTHOR]

Nano/microparticles with hollow structures have many applications in various fields. However, engineering hollow covalent organic framework (COF) particles in a simple and efficient manner remains a significant challenge. In this study, we propose a self‐template crystallization method to prepare imine‐based COF microparticles with tailored shell thickness and high crystallinity. This method involves the post‐transformation of amorphous microparticles in a highly reversible reaction system containing monofunctional competitors. The amorphous precursors with high‐Gibbs free energy decompose and reconstruct to form highly crystalline COFs in situ on the particle surface. This process allows for the preparation of various Schiff‐base COF particles with good crystallinity and tailored hollow structures, with diameters ranging from 120 to 680 nm and shell thicknesses of 27–96 nm. These COF particles have well‐defined micropore sizes centered between 1.0 and 4.0 nm and a high‐specific surface area of up to 543 m2 g−1. The resulted COF particles could be used to support ethylene oligomerization catalysts for improving their activity and selectivity, that is, the mass fraction of α‐olefins above C10 increased from almost zero to 52.7% after COF supporting. Our method thus provides an efficient way to precisely tailor the microstructure and morphology of COF materials for advanced applications. [ABSTRACT FROM AUTHOR]

All‐optical neural networks have advantages in higher throughput, higher speed as well as lower energy consumption compared to electrical neural networks. Optical neural networks have already shown great potential in various applications; however, the operation speed of the network is limited by the 2D detector as most optical neural networks rely on space to space projection. Here, a space to time projection approach to build diffractive deep neural network (D2NN) is proposed, which can project spatial intensity distribution into time‐domain intensity variation, thus bypassing the detection speed limit of 2D imaging device. Based on this scheme, high‐speed all‐optical logic gates are theoretically analyzed and experimentally realized. In this case, the network's operation speed is only limited by the photodetector (PD), which can reach GHz levels. Moreover, the method will show great advantage when it comes to wavelengths where 2D detectors are not achievable easily such as infrared, terahertz or microwaves. [ABSTRACT FROM AUTHOR]

Neural network accelerator based on photonic‐integrated circuits is emerging as a promising technology for fast, power‐efficient, and parallel computing. Under such technology, optics is mainly used for linear transformations, e.g., through an array of cascaded switching networks. Nonlinear activation is implemented either electronically requiring extra optical–electrical conversion or via nonlinear optical materials that often suffer from high loss, large power consumption, and difficulty in integration. Herein, an optical neural chip with only one multimode waveguide, fabricated using low‐cost linear optical materials, plus seven heater electrodes to control the multimode interference, is proposed. The nonlinear networks are intrinsically integrated in the electrical‐to‐optical signal conversion through the waveguide. The linear computation, in the electronic domain, is included in the mandatory step to convert the input matrix to the intermediate current values on the seven electrodes. Though extremely simple, the proposed system can classify nonlinear datasets and images by optical readout with high accuracy and without calibration. Prospects for future development are given at the end. In this work, an alternative route is offered to exploiting the classic multimode interference for advanced optical computing applications. [ABSTRACT FROM AUTHOR]

In this work, an environmentally‐friendly deep eutectic solvent (DES) was employed as a catalyst to generate polyvinyl butyral (PVB) resins from polyvinyl alcohol (PVA) with a weakly acidic polymer (polyacrylic acid [PAA]) as an emulsifier. Finally, high viscosity PVB resins with molecular weight of 110,000–200,000 g · mol−1 and acetalization degree above 83% were successfully synthesized, which was found to satisfy the requirements for interlayer films between safety glass. Furthermore, it was well proved that the properties of PVB resins immensely depend on the molecular structures of the PVA. The molecular weight of the PVB, independent of alcoholic degrees of the PVA, indicated an upward trend with the increase of the molecular weight of the PVA. As for these four PVBs with high molecular weight, the Tg was sensitive to the content of hydroxyl and acetal groups rather than molecular weight, associated with the inter‐ or intra‐molecule hydrogen bond between OH. PVB‐1799 and PVB‐1797 had higher Ti and Tg than that of PVB‐1788 and PVB‐1795 because the former had low contents of vinyl acetate group (VAc) and alcohol hydroxyl group (VOH). The tensile strength of PVBs was all higher than 30 Mpa, and the elongation at break was about 300% due to their high molecular weights. [ABSTRACT FROM AUTHOR]

The loading of homogeneous catalysts with support can dramatically improve their performance in olefin polymerization. However, the challenge lies in the development of supported catalysts with well‐defined pore structures and good compatibility to achieve high catalytic activity and product performance. Herein, we report the use of an emergent class of porous material—covalent organic framework material (COF) as a carrier to support metallocene catalyst—Cp2ZrCl2 for ethylene polymerization. The COF‐supported catalyst demonstrates a higher catalytic activity of 31.1×106 g mol−1 h−1 at 140 °C, compared with 11.2×106 g mol−1 h−1 for the homogenous one. The resulting polyethylene (PE) products possess higher weight‐average molecular weight (Mw) and narrower molecular weight distribution (Ð) after COF supporting, that is, Mw increases from 160 to 308 kDa and Ð drops from 3.3 to 2.2. The melting point (Tm) is also increased by up to 5.2 °C. Moreover, the PE product possesses a characteristic filamentous microstructure and demonstrates an increased tensile strength from 19.0 to 30.7 MPa and elongation at break from 350 to 1400 % after catalyst loading. We believe that the use of COF carriers will facilitate the future development of supported catalysts for highly efficient olefin polymerization and high‐performance polyolefins. [ABSTRACT FROM AUTHOR]

Atopic dermatitis (AD) is a common inflammatory skin disorder. Mast cells play an important role in AD because they regulate allergic reactions and inflammatory responses. However, whether and how the modulation of mast cell activity affects AD has not been determined. In this study, we aimed to determine the effects and mechanisms of 3‐O‐cyclohexanecarbonyl‐11‐keto‐β‐boswellic acid (CKBA). This natural compound derivative alleviates skin inflammation by inhibiting mast cell activation and maintaining skin barrier homeostasis in AD. CKBA markedly reduced serum IgE levels and alleviated skin inflammation in calcipotriol (MC903)‐induced AD mouse model. CKBA also restrained mast cell degranulation both in vitro and in vivo. RNA‐seq analysis revealed that CKBA downregulated the extracellular signal‐regulated kinase (ERK) signaling in BM‐derived mast cells activated by anti‐2,4‐dinitrophenol/2,4‐dinitrophenol‐human serum albumin. We proved that CKBA suppressed mast cell activation via ERK signaling using the ERK activator (t‐butyl hydroquinone) and inhibitor (selumetinib; AZD6244) in AD. Thus, CKBA suppressed mast cell activation in AD via the ERK signaling pathway and could be a therapeutic candidate drug for AD. [ABSTRACT FROM AUTHOR]

Direct conversion of cyclohexane to adipic acid (AA) under mild conditions is an attractive technology in response to the increasing industrial demand of chemical intermediate AA. Exploring advanced free radical oxidation systems is the key to converting cyclohexane in a direct and mild manner. This study demonstrates that electrocatalytic water oxidation can quantitatively generate hydroxyl radicals (⋅OH) to selectively oxidize cyclohexane to AA by a vanadium oxide (VOx)‐platinum (Pt) composite catalyst coupled with persulfate (PS) redox mediator at the electrode/electrolyte interface under ambient temperature and pressure. The three active components of VOx, Pt, and PS can produce different concentrations of ⋅OH radicals alone or in combination, resulting in different AA selectivity and cyclohexane conversion, and the activity increased with the increase of free radical concentration before AA peroxidation. The optimized ternary oxidation system of VOx‐Pt‐PS achieved a cyclohexane conversion of 85 % with 95 % AA selectivity and the corresponding yield was 81 %, better than most traditional oxidation systems. Electrochemical interfaces‐driven radical oxidation provides opportunities to oxidatively convert many other inexpensive hydrocarbons to value‐added chemicals. [ABSTRACT FROM AUTHOR]

Summary: In the current research, we have adopted a pH shift treatment method that can significantly improve the solubility and emulsification of rice protein isolate (RPI) under neutral conditions. Our results showed that the RPI reached a quasi‐equilibrium state at 1 h after alkali shift treatment, and the solubility and emulsifying properties of RPI were significantly improved compared with the control. In addition, the particle size of RPI decreased considerably under the alkali shift treatment. The results of electron microscopy showed that the RPI aggregates were depolymerised and the particle size distribution was more uniform. The pH shift treatment induced the rearrangement of protein secondary structure, and the exposure of hydrophobic groups increase the surface hydrophobicity of RPI. The change in endogenous fluorescence spectrum, UV and the disulfide bond content all showed that the conformation of RPI changed significantly through pH shift treatment. In addition, it was found that the RPI treated under pH 10–11 shift possessed the best property to stabilise the emulsion. This study showed that under the condition of pH10 and pH11 shift treatment, the structural and functional properties of RPI were vastly improved, and the application of RPI in food was greatly ameliorated. [ABSTRACT FROM AUTHOR]

Block copolymer‐based organic solar cells (OSCs) possess better stability than their binary all‐polymer counterparts; thus, promoting the power conversion efficiency (PCE) of them to a higher level would be meaningful to achieving a higher level of efficiency–stability balance. Herein, two‐step annealing combining solvent vapor and thermal annealing (TA) upon cast films is deployed and 15% efficiency for block copolymer PM6‐b‐PY‐IT‐based OSCs is realized, which appeals to the level of traditional binary all‐polymer solar cells. The morphology optimization of the properly enhanced crystallite size, global crystallinity, and reduced pure phase length scale and maintained phase purity are supposed to be the driving force of increase device performance. This work offers a high PCE for the typical type of solar cell, brightening the prospect of realizing OSCs' application. [ABSTRACT FROM AUTHOR]

The interaction of 2D materials with ultrashort laser excitation generates fiber soliton pulses with extreme nonlinear absorption characteristics, which are essential for generating ultrafast pulses. However, searching for suitable nanomaterials to achieve versatile photonic properties is difficult. Factors such as cost, manufacturing process complexity, optical response time, and nonlinear absorption effects make the balance between high performance and low cost a constant challenge, greatly hindering the research and development of ultrafast photonics technology. For fiber soliton pulse systems, γ‐MnO2, as a transition metal oxide (TMO), shows excellent potential among many candidate nanomaterials due to its rich narrow‐band optoelectronic microstructural features and nonlinear optical properties. In this work, this fundamental trade‐off is overcome and γ‐MnO2 is investigated as a nonlinear optical material for multifunctional fiber soliton pulsed lasers. The outputs of conventional soliton pulses, 23rd order harmonic soliton‐molecule picosecond pulses, continuous and soliton pulse waves coexist in dual‐wavelength, and soliton rain pulses are obtained simultaneously, successfully achieving a technological breakthrough in nanophotonics and pulse dynamics. It is demonstrated that MnO2 has a broad application prospect for generating nonlinear effects such as fiber optic soliton pulses, which provides an effective and rich theoretical support for developing ultrafast photonics of narrow‐band optoelectronic materials. [ABSTRACT FROM AUTHOR]

To improve the low‐temperature activity and anti‐sintering ability of Ni‐based catalyst for CO2 methanation, nickel catalysts supported on ZrO2, CeO2 and Ce−Zr−O solid solutions are prepared via citrate complexation‐impregnation method, and characterized by BET, TPR, CO2‐TPD, H2‐TPD, XRD, XPS, TEM and ICP. The relationship between the structure and catalytic performance is also investigated systematically. The results show that Ni/Ce0.2Zr0.8O2 catalyst exhibits the highest CO2 conversion of 71 % at 250 °C and the highest stability, which is mainly attributed to the high dispersion of active metal nickel and its small particle size. The optimized interaction between Ce−Zr−O solid solution and Ni is in favor of the high dispersion and the stability of Ni nanoparticles on the surface, and enhances the sintering resistance of Ni catalyst. In addition, the similar TOF values of catalysts in different supports indicate that for improving low‐temperature activity of this system, the dispersion of Ni NPs is critical. [ABSTRACT FROM AUTHOR]

The rapid development of the electronic packaging industry imposes stringent requirements on epoxy resin insulation materials for lower water absorption and higher insulation properties. Here, hydroxy‐terminated polydimethylsiloxane (HTPDMS) was grafted on the molecular chain of the epoxy resin for enhanced waterproof and insulating properties of the epoxy resin. The HTPDMS‐modified epoxy resin specimens were prepared and subjected to water absorption and water absorption insulation performance tests. The experimental results indicated that the water absorption rate of the modified epoxy resin was reduced by 34.2%, resulting in a 25.2% reduction of the dielectric loss, an 11.6% increase of the breakdown strength, and a 98.3% increase of the volume resistivity. The satisfactory performance of the HTPDMS‐modified epoxy resin insulation material is attributed to the low surface energy and flexible SiO bond of the introduced HTPDMS. Simultaneously, the reduction of surface defects is also conducive to the epoxy resin insulation performance. Thus, HTPDMS‐modified epoxy resin insulation materials can maintain excellent insulation properties in humid environments, making them a promising application in the field of electronic packaging. [ABSTRACT FROM AUTHOR]

Increases in rated voltage and power density of high voltage gas insulated switchgears (GIS) impose stringent requirements on the diglycidyl ether of bisphenol A (DGEBA)‐anhydride thermoset, which is widely used as insulation materials for high GIS, for higher mechanical and heat‐resistant properties. In this paper, 3,4‐epoxycyclohexylmethyl 3,4‐epoxycyclohexanecarboxylate (AOO) was copolymerized with DGEBA ‐anhydride system to increase the mechanical and thermal properties of the thermosets. Based on the molecular dynamics simulation method, the coefficient of thermal expansion, glass transition temperature (Tg), and modulus of AOO copolymer‐modified DGEBA‐anhydride thermosets were calculated. The AOO copolymer‐modified DGEBA‐anhydride thermosets specimens were further experimentally prepared and subjected to differential scanning calorimeter test, TGA test, tensile bending test, and dielectric test. The results of simulation and experiment simultaneously indicated that the Tg and modulus of the DGEBA‐anhydride thermoset are enhanced after AOO modification. This is mainly due to the decrease in free volume percentage and mean square displacement of the epoxy cross‐linked network structure after the introduction of AOO molecules, which makes the structure more compact and the cross‐link density increased. Additionally, the dielectric performances of the thermoset was enhanced by AOO. The excellent thermal, mechanical and dielectric properties of AOO modified DGEBA‐anhydride thermoset make it a promising application in the field of high voltage GIS. [ABSTRACT FROM AUTHOR]

The phase segregation as a result of mixing organic semiconductors with polymeric additives has been reported as an intriguing avenue to optimize semiconductor crystal microstructure, active layer composition and charge carrier transport. In this work, we report the mixing of organic semiconductor 6,13‐bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) with poly(butylacrylate) as a polymer additive to control the semiconductor crystal growth and morphology. The incorporation of poly(butylacrylate) induces a vertical phase segregation but a more predominant lateral phase segregation with TIPS pentacene. Along with a solvent vapor annealing technique, poly(butylacrylate) evenly distributes the semiconductor nuclei on the polymer matrix, and results in organic crystal with enlarged grain width. In addition, the randomized crystal growth of TIPS pentacene has been significantly reduced, giving rise to a 25‐fold decrease in misorientation angle. The bottom‐gate, top‐contact thin film transistors with the poly(butylacrylate)/TIPS pentacene mixture as the active layer demonstrated an improved hole mobility of 0.11 cm2/Vs. We believe the phase segregation induced by the poly(butylacrylate) polymer as well as the solvent vapor annealing method as reported in this work can be facilely replicated on other organic semiconductors to realize high performance organic electronic device applications. [ABSTRACT FROM AUTHOR]

In the ongoing quest to develop lithium‐ion batteries with superior capacity and enhanced safety, the focus has shifted toward all‐solid‐state batteries (SSBs) and nickel‐rich cathode materials. Despite their promise, these technologies face significant interface challenges, notably poor contact and low ion transport efficiency, leading to substantial stability issues. This review aims to provide a comprehensive analysis of both the advantages and the challenges associated with all‐solid‐state batteries. In addition, it discusses the benefits of single‐crystal application in SSBs, in terms of their kinetic performance, mechanical properties, and stability. The review concludes by proposing various strategies to optimize single‐crystal technologies, targeting the development of efficient nickel‐rich single‐crystal materials for use in all‐solid‐state batteries. These approaches offer the potential to address the core challenges currently faced by SSBs and pave the way for the next generation of high‐performance batteries. [ABSTRACT FROM AUTHOR]

Cover Feature: Covalent Organic Framework-Supported Metallocene for Ethylene Polymerization (Chem. Eur. J. 54/2023) Covalent organic frameworks, ethylene polymerization, heterogenous polymerization, polyolefins, supported metallocenes Keywords: covalent organic frameworks; ethylene polymerization; heterogenous polymerization; polyolefins; supported metallocenes EN covalent organic frameworks ethylene polymerization heterogenous polymerization polyolefins supported metallocenes 1 1 1 09/29/23 20230926 NES 230926 B Covalent organic framework b (COF) particles with hydroxy groups and well-defined micropores have been synthesized and used as novel carriers to load a metallocene catalyst - Cp SB 2 sb ZrCl SB 2 sb . [Extracted from the article]

Reinforced concrete shear walls in multistory buildings often undergo the combined action of vertical and horizontal loads, with their failure primarily attributed to localized damage of the concrete at the bottom of edge elements, leading to premature loss of wall functionality. To enhance the performance of shear walls, this study explores the optimization of shear wall design from the perspective of the stress path within the wall, introducing a diagonally distributed reinforcements in shear walls (referred to as DDR shear walls). To investigate the seismic performance of DDR shear walls, we consider the effects of axial compression ratio, the inclination angle of distributed reinforcing bars, reinforcing bar spacing, and shear span ratio. We design 27 shear wall models with various parameter combinations and employ ABAQUS finite element analysis software to simulate the seismic performance. The simulation results reveal that the inclined distribution of reinforcing bars significantly enhances the seismic performance of shear walls. To achieve optimal structural performance, the inclination angle of reinforcing bars should be adjusted for different floor levels, with higher floors requiring a greater angle and lower floors a smaller one. Additionally, increasing the reinforcing bar spacing and altering the shear span ratio will have varying degrees of impact on the seismic performance of shear walls, necessitating rational design adjustments based on specific circumstances. Furthermore, the application of DDR shear walls in prefabricated construction can be considered to optimize construction processes. [ABSTRACT FROM AUTHOR]